基于矢量控制车辆交流异步电机控制系统分析

Modeling and Analysis of Vehicle AC Asynchronous Motor Control System Based on Vector Control

交流异步电机结构简单、运行可靠且成本低,特别适合于大型电传动自卸车的轮边驱动系统,而非线性特征对控制系统提出较高要求。根据某车辆交流异步电机的运行特点,获取关键特征参数描述方程;基于矢量控制原理,对电机的控制系统进行设计,搭建控制模型;基于Simulink搭建控制系统的分析模型,对模型的转速和转矩控制进行验证分析;选取单次和两次阶跃转速、缓慢加速及带负载运行等工况进行分析,获取转速、输出转矩、电流等参数变化情况;参考实际车辆的运行特征,搭建异步交流电机控制系统测试台架,选取不同负载工况运行,对控制系统的特性进行分析,并对数学模型和仿真模型进行验证。分析结果可知:采用矢量控制系统,电机运行转态良好;不同的运行工况下,电机响应迅速,关键参数波动较小,整体保持稳定;在控制系统作用下,基频以下运行时,通过电压补偿,实现了恒转速调速运行;而超过基频率时,满足负载工况的情况下,系统实现了恒功率调速;电机的效率最高达到90%以上,随负载增加而提升,控制系统使得电机呈现出良好的优势;试验测试结果表明所搭建的控制系统是有效的,分析模型是可靠的,为此类设计研究提供参考。

AC asynchronous motor has the advantages of simple structure,reliable operation and low cost.It is especially suitable for the wheel drive system of large electric drive dump truck,and the nonlinear characteristics put forward higher requirements for the control system.According to the operation characteristics of a vehicle AC asynchronous motor,the characteristic parameter description equation was obtained.Based on the principle of vector control,the control system was designed,the analysis model of the control system was built based on Simulink,and the model speed and torque control were verified.The single and double step speed,slow acceleration and load operation was selected to test,and the changes of speed,output torque and other parameters were obtained.With reference to the actual vehicle characteristics,the test bench of asynchronous AC motor control system was built,and the characteristics of the control system under different load conditions were selected for verification.The analysis results show that the motor runs well in the control system built by vector control.Under different operating conditions,the system responds quickly,the parameter fluctuation is small,and the overall stability is maintained.Under the action of the control system,when operating below the fundamental frequency,the constant speed regulation operation is realized through voltage compensation.When the fundamental frequency is exceeded and the load condition is met,the system realizes constant power speed regulation.The maximum efficiency of the motor is more than 90%,which increases with the increase of load.The control system makes the motor show good advantages.It shows the reliability of the control model and provides a reference for this kind of design research.